Corn castoff is a term used to describe the COB of corn that is left behind after the kernels have been removed. It is also known as corn husk, which is the outer covering of the corn kernel. The COB is usually discarded after the kernels are harvested, but it can be used for various purposes such as making animal feed, fuel, and even decorations. The three-letter acronym COB stands for Corn On the COB.